hmmmm
perhaps somthing genetic?
i found these most common illnesses onthe net:
Mites -
Although mostly uncommon in a private herp collection, mites are another possible complication. They will most likely be noticed first around the eyes or the corners of the mouth as little round, black/brown creepy creatures. They can be treated by many commercial products available at a local pet shop or by a veterinary strength solution available from your veterinarian.
Be sure to follow the directions on the product. Treatment of mites usually takes close to a month of continuous care... as eggs can hatch daily and must be 'taken care of' ASAP... these little bugs have an extraordinary reproductive rate. If you have more than the 1 infested reptile, take extra precautions not to transfer the mites from one to another.
Terminal Ingestion -
Unfortunately, young dragons will swallow larger food items than are appropriate for their size. They can die from the large food item lodging within their digestive tract. If this were to occur they will extend their hind limbs straight back as though paralyzed or in excruciating pain. You can raise your basking temperature or soak the dragon in some warm water to possibly induce a bowel movement - but success is a long shot. (Note that lounging/basking dragons often extend their hind limbs. Do not confuse this posture with the indigestion-induced paralysis, in which the legs remain extended and are unable to move. If your dragon can walk, it is just being a lounge lizard.)
Thermal Burns -
These are caused by direct contact with a heat source and scald the skin - most likely resulting in blisters. The blisters often break open and create the opportunity for secondary bacterial infections, which not only complicate treatment, but also could possibly be fatal (depending on the severity). Dragons WILL walk through their feces - so an impeccable cage is necessary during treatment. While daily treatment can be taken care of at home - your veterinarian should perform initial diagnosis and follow-ups.
Calcium Deficiency -
Without adequate calcium and vitamin D3 in your Dragon's diet, aside from a slow growth rate, you will more than likely encounter Metabolic Bone Disease. The first symptom usually noticed is uncontrolled twitching of the dragon’s toes or legs. This can be a fatal disease if not treated promptly. If this problem occurs, we suggest raising the amount of calcium in the Dragons diet immediately and taking it outside in direct sunlight to bask for a period of time each day until the twitching stops. If there is no change in a few days, consider veterinary care as an option.
Vitamin A Toxicity -
This is a common problem that occurs when dragons are over supplemented. Many multi-vitamins contain levels of VitA and should be offered sparingly. Toxicity is characterized by a swelling of the throat and eyes, and proceeding to a bloating of the body and lethargy.
Respiratory Infections -
The Bearded Dragon is very resistant to respiratory infections. BUT... prolonged exposure to low temperatures, improper humidity and poor cage conditions could result in respiratory complications. Treatment for this problem... usually antibiotics and to raise the ambient temperature of your cage a bit. (The best thing is to avoid low cage temperatures and eliminate the problem before it arises.) The most obvious symptoms are gaping, forced exhalation of air, puffing of the throat, a puffed up appearance of the body and lack of appetite. In some cases, the mucus may accumulate in the mouth and/or emerge from the nostrils. If these symptoms are present and persistent the illness is usually well progressed - a veterinarian visit is in order immediately for treatment.
Internal Parasites -
Symptoms of internal parasites include weight loss, worms in the stools, runny stools, gaping and listlessness. If you observe a combination of these symptoms, you should take your bearded dragon to a veterinarian to have a stool sample examined to determine if there are any parasites present and if so, what kind they are. Follow their recommendation for treatment.